JP2018016370A - Packaging bag for alcohol content - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a packaging bag for alcohol content which is excellent in alcohol resistance and heat sealability and is excellent in hand tearability at the time of opening.SOLUTION: A packaging bag for alcohol content is formed of a laminate having a base material layer, an adhesive layer, a barrier layer, an anchor coat layer and a polyolefin-based resin layer laminated in this order, where the barrier layer is a vapor-deposition film of aluminum foil or aluminum oxide and silicon oxide, the anchor coat layer is formed by applying an aqueous dispersion liquid, which is obtained by dispersing a polyolefin copolymerization resin that contains unsaturated carboxylic acid or its anhydride and acrylate and has a specific melting point and a melt flow rate so that the number average particle diameter is 1 μm or less and contains no non-volatile water-based auxiliary, onto a barrier layer surface, so that a thickness at the time of drying is 0.1-2 μm, heating and drying the aqueous dispersion liquid, and the polyolefin resin layer is formed by extrusion coating a polyolefin resin onto an anchor coat layer surface or extrusion laminating a polyolefin resin on the similar polyolefin resin.SELECTED DRAWING: Figure 1

Description

  The present invention has a high resistance to components such as organic compounds contained in the contents of pharmaceuticals, cosmetics, chemicals, foods, etc., particularly high concentrations of alcohol. In addition, the invention relates to a packaging material excellent in alcohol resistance having a sealant layer excellent in heat sealability, and a packaging container using the packaging material, that is, a packaging bag for alcohol-containing materials.

Conventionally, as a packaging bag for sealing and packaging alcohol-containing materials, for example, a packaging bag produced by heat-sealing a laminate in which a base material layer, a barrier layer, a sealant layer, and the like are laminated via an adhesive layer has been used. It was.
However, when the content to be packaged is a high concentration alcohol of 50% by mass or more, for example, the alcohol component penetrates into the laminate during long-term storage, and in particular, the adhesive layer between the barrier layer and the sealant layer. As a result, there was a problem that the sealant layer peeled off (delamination) from the barrier layer and the packaging bag was damaged.

  As a method of laminating a sealant layer on the barrier layer, generally, an anchor coat layer is provided as an adhesive layer on the barrier layer surface, and a resin of the sealant layer is extruded thereon to laminate as a coat, or a film is previously formed on the barrier layer surface. A method is used in which the film of the sealant layer formed above is laminated by a dry laminating method using a dry laminating adhesive such as a two-component curable polyurethane adhesive.

As anchor coating agents (AC agents) used for the anchor coat layer, AC agents such as organic titanium AC agents, isocyanate AC agents (urethanes), polyethyleneimine AC agents, polybutadiene AC agents are commercially available. Yes.
However, when the content of the alcohol is a high-concentration alcohol, the alcohol resistance is insufficient, and the temperature of the packaging material in which the content is sealed and packaged is 60%, for example, as an accelerated test. When a storage test of about one month was performed at ° C, there was a problem that the barrier layer peeled off from the sealant layer.

Similarly, when the sealant layer is bonded to the barrier layer by the dry laminating method, the alcohol resistance of the adhesive for dry laminating is insufficient, and the sealant layer peels from the barrier layer according to the storage test. There was a problem.
Moreover, the AC agent and the adhesive for dry laminating, except for some of them, use an organic solvent for the coating solution. there were.
As techniques related to these, the following are known.
For example, a film laminated with a polyurethane adhesive layer containing a urea bond and a sealant film contains a material containing a strong permeable substance, an acidic substance, an alkaline substance, a fragrance, an oil, a surfactant, and a high-boiling organic solvent. Packaging bags are known.

That is, the invention relates to ink bags for ink jet devices and flexible packaging bags for foods, detergents, household items, health and medical products, etc., and the content to be stored is strong penetration of alcohols, bathing agents, poultices, etc. Even if it contains a strong permeable substance containing a volatile component with strength, it does not cause delamination without reducing the adhesive strength of the adhesive layer of the plastic laminated film that constitutes the bag. For the purpose of providing a flexible packaging bag with excellent storage stability of contents, a base film and a sealant film made of a polyethylene film with no additive added are passed through a polyurethane adhesive layer containing urea bonds. There has been known an invention for obtaining a flexible packaging bag by using a laminated film laminated (see Patent Document 1).

  In addition, the laminate in which the anchor coat layer is composed of an anchor coat agent containing 85% by mass or more of a compound having two or more isocyanate groups does not lower the laminate strength of the contents even when filled with alcohol. It has been known.

  That is, it is a laminate having an aluminum foil layer excellent in gas barrier properties and the like, and particularly when used as various packaging materials, even when a strong permeable material containing a volatile material such as alcohol is packaged, the initial excellent laminate strength For the purpose of providing a laminate in which the laminate strength between each layer is not lowered, and for that purpose, a hydrothermal modification layer is formed on at least one surface of the aluminum foil layer by hydrothermal modification treatment. On the hydrothermally modified layer, an anchor coat layer, an adhesive resin layer, an anchor coat layer, and a plastic substrate layer are at least laminated in this relative order, and the anchor coat layer is an isocyanate group. There is known an invention in which a laminated body is constituted by an anchor coating agent containing 85% by mass or more of a compound having two or more (Patent Document 2) Irradiation).

Further, in a container laminate in which a heat-sealable resin layer is laminated on at least the content side of the base material sheet, silicon is bonded directly to the base material sheet side of the innermost heat-sealable resin layer on the content side. A laminate for a container provided with an oxide vapor deposition layer is known.
However, these techniques are not satisfactory in terms of alcohol resistance and heat sealability.

Furthermore, in the laminate in which the resin for the sealant layer is extruded and laminated on the barrier layer, the anchor layer is not provided on the barrier layer surface, and an aluminum foil is used as the barrier layer, and the metal such as aluminum foil is excellent. There is known a laminate obtained by using an ethylene-methacrylic acid random copolymer (EMAA resin), which is said to exhibit adhesiveness, as a resin for a sealant layer, and extrusion-coating it directly onto an aluminum foil surface.
However, the EMAA resin is more expensive than a resin such as polyethylene, is inferior in sealing properties, and has a problem that tearability when opening a packaging bag, that is, hand cutting properties is not good.

JP 2013-95454 A JP 2009-172824 A

  The present invention solves the above-mentioned problems and provides an alcohol-containing packaging bag having excellent alcohol resistance, excellent heat sealability, and excellent hand tearability when opening the bag. This is the issue.

  As a result of various studies, the inventor is a packaging bag formed of a laminate formed by laminating at least a base layer, an adhesive layer, a barrier layer such as an aluminum foil, an anchor coat layer, and a polyolefin resin layer in this order. The anchor coat layer is formed by applying a specific aqueous dispersion containing a polyolefin copolymer resin containing an unsaturated carboxylic acid or an anhydride thereof and a (meth) acrylic ester on the barrier layer and drying it. It has been found that a packaging bag characterized by being a layer achieves the above object.

The present invention is characterized by the following points.
1. A packaging bag for packaging a liquid having an alcohol concentration of 50% by mass or more, or an impregnated product of the liquid, the packaging bag comprising at least a base material layer, an adhesive layer, a barrier layer, an anchor coat layer, and a polyolefin resin layer. It is formed of a laminate that is laminated in this order,
The barrier layer is an aluminum foil, or a deposited film formed by depositing aluminum oxide or silicon oxide on a base film,
The anchor coat layer is an aqueous dispersion in which a polyolefin copolymer resin is dispersed so that the number average particle diameter thereof is 1 μm or less, and the aqueous dispersion does not contain a non-volatile aqueous agent. The aqueous dispersion formed is applied to the surface of the barrier layer so that the thickness upon drying is 0.1 to 2 μm, and is formed by heating and drying to improve the barrier property against alcohol,
The polyolefin copolymer resin contains 0.01 to 5% by mass of an unsaturated carboxylic acid or an anhydride thereof, 1 to 20% by mass of a (meth) acrylic acid ester, and a melting point of 90 to 110 ° C. The melt flow rate (MFR) is 1-10 g / 10 min,
The polyolefin-based resin layer is formed by a method of extruding and coating a polyolefin-based resin on the surface of the anchor coat layer, or a method of extruding and laminating a polyolefin-based resin film using a similar polyolefin-based resin. A packaging bag for alcohol-containing materials.
2. The above 1 is characterized in that the base material layer is a biaxially stretched polyethylene terephthalate film, the barrier layer is an aluminum foil, and the polyolefin resin layer is a layer made of low density polyethylene or linear low density polyethylene. A packaging bag for alcohol-containing materials as described in 1.

As described above, the packaging bag of the present invention is formed by heat-sealing a laminate for an alcohol-containing material, in which a base material layer, an adhesive layer, a barrier layer, an anchor coat layer, and a polyolefin resin layer are laminated in this order. The anchor coat layer is formed by using an aqueous dispersion in which a specific polyolefin copolymer resin is dispersed so that its number average particle diameter is 1 μm or less.
And this specific polyolefin copolymer resin contains unsaturated carboxylic acid or its anhydride in 0.01-5 mass%, and contains (meth) acrylic acid ester in 1-20 mass%. And the melting point is 90 to 110 ° C., the MFR is 1 to 10 g / 10 min, and the aqueous dispersion is formed so as to be substantially free of non-volatile aqueous additive, Is an invention wherein the barrier layer surface is formed by coating, heating and drying so that the thickness upon drying is 0.1 to 2 μm.

  The barrier layer is an aluminum foil, or a vapor deposition film obtained by vapor-depositing aluminum oxide or silicon oxide on a base film, and the polyolefin resin layer is formed by extruding a polyolefin resin on the surface of the anchor coat layer. Or a packaging bag for an alcohol-containing material, wherein the polyolefin-based resin film is formed by extrusion lamination using a similar polyolefin-based resin.

  The anchor coat layer of the packaging bag for alcohol-containing material of the present invention is an aqueous dispersion containing the specific polyolefin copolymer resin as described above but not containing a non-volatile water-immobilizing aid, and the polyolefin copolymer resin Is a layer obtained by applying an aqueous dispersion liquid in which the number average particle size is dispersed in an aqueous solvent so that the number average particle diameter thereof is 1 μm or less onto a barrier layer such as an aluminum foil, and drying and curing.

Therefore, a uniform anchor coat layer with no defects such as pinholes is formed, resistance to alcohol contained in contents such as pharmaceuticals, cosmetics and foods is improved, and the contents of strong alcohol components are stored for a long period of time. In addition, stable laminate strength and seal strength can be maintained.

In addition, even if the barrier layer is an aluminum foil or a vapor deposited film on which aluminum oxide or silicon oxide is deposited, it exhibits high interlayer adhesion strength, and further exhibits excellent initial adhesiveness. Can prevent unintended peeling. Moreover, since the polyolefin resin layer (sealant layer) is firmly heat bonded to the anchor coat layer surface, it exhibits excellent interlayer adhesion strength.
Furthermore, the packaging bag of this invention can reduce the discharge | emission amount of the organic solvent at the time of manufacture, and is excellent in the hand cutting property at the time of opening.

It is a schematic sectional drawing which shows an example about the laminated constitution of the laminated body used for the packaging bag for alcohol containing materials of this invention. It is a schematic sectional drawing which shows an example about the laminated constitution of the laminated body used for the packaging bag for alcohol containing materials of this invention.

(1) Configuration of Alcohol-Containing Material Packaging Bag and Laminate Used in the Alcohol-Containing Product Packaging Bag The alcohol-containing packaging bag of the present invention is characterized by the configuration of the laminate used in the production of the packaging bag. For example, FIG. It can be manufactured by heat-sealing a laminate having a structure as shown in FIG. Therefore, the form of the bag itself is not particularly limited. For example, a three-side seal type or four-side seal type bag, a flat bag such as a pillow type bag, a self-standing bag such as a standing pouch, or a gusset bag. Any type of bag may be used.
Further, as described above, the content sealed and packaged in the packaging bag for alcohol-containing material of the present invention is a liquid having an alcohol concentration of 50% by mass or more, or an impregnation product of the liquid. There is no particular limitation on itself, for example, methyl alcohol, ethyl alcohol, monohydric alcohols such as propyl alcohol, butyl alcohol, and amyl alcohol including various isomers, as well as many such as ethylene glycol, polymethylene glycol, and glycerin. Any of alcohols and the like may be used.

FIG. 1 is a schematic cross-sectional view showing the basic structure of a laminate used in the packaging bag for alcohol-containing materials of the present invention.
A laminated body 10 shown in FIG. 1 is configured by laminating a base material layer 1, an adhesive layer 2, a barrier layer 3, an anchor coat layer 4, and a polyolefin resin layer 5 in this order from the top.

When producing a packaging bag for alcohol-containing material using this laminate 10, the polyolefin resin layer 5 is used as a sealant layer, and the polyolefin resin layer 5 is directed to the inner surface side of the bag. The laminated body 10 is arrange | positioned, it heat-seals and forms a bag. This also applies to the laminate 20 shown in FIG.
The laminated body 20 shown in FIG. 2 has the same laminated structure as that of the laminated body 10 shown in FIG. 1, from the upper side in the drawing, from the upper side, the base material layer 1, the adhesive layer 2, the barrier layer 3, and the anchor coat layer. 4, the polyolefin resin layer 5 is laminated in order, but the difference from the laminate 10 shown in FIG. 1 is that when the packaging bag for alcohol-containing material is manufactured using the laminate 20, It is that the unevenness | corrugation 6 whose height is several micrometers-20 micrometers is provided in the whole surface of the polyolefin-type resin layer 5 used as an inner surface side.
Next, each layer which comprises the packaging bag for alcohol containing materials of this invention is demonstrated concretely.

(2) Base material layer The base material layer which comprises the packaging bag for alcohol containing materials of this invention should just be a film and a sheet | seat which can ensure the intensity | strength as a packaging material.
Specific examples of such films and sheets include paper, polyolefin resins such as aluminum foil polyethylene resin or polypropylene resin, such as low density polyethylene, medium density polyethylene, high density polyethylene, and linear low density polyethylene. , Stretched polypropylene, K-coated stretched polypropylene, cyclic polyolefin resin, K-coated stretched nylon, polyvinyl alcohol, polyacrylonitrile, ethylene-vinyl acetate copolymer resin, ionomer resin, ethylene- (meth) acrylic acid copolymer resin, ethylene -(Meth) acrylate copolymer resin, ethylene-propylene copolymer, acrylonitrile-styrene copolymer, acrylonitrile-butadiene-styrene copolymer, methylpentene resin, polybutene resin, acid modification Polyolefin resins, polyamide resins such as various nylons, polystyrene resins, low crystalline saturated polyesters or amorphous polyester resins, for example, polyester resins such as polyethylene terephthalate and polyethylene naphthalate, polyvinyl chloride, polychlorinated Vinylidene, polyvinylidene fluoride, ethylene tetrafluoroethylene resin, polyethylene tetrafluoroethylene resin, polycarbonate resin, polyurethane resin, acetal resin, cellulose resin, and the like can be used.

In the present invention, among the above-mentioned resins, it is preferable to use a polyester resin, polyolefin resin, or polyamide resin film or sheet, and in particular, a biaxially stretched polyester film such as a biaxially stretched polyethylene terephthalate film. It is preferable to use a biaxially stretched nylon film, a biaxially stretched polypropylene film or the like, particularly a biaxially stretched polyethylene terephthalate film.
In the present invention, the thickness of the base film is preferably from 0.1 to 300 μm, more preferably from 1 to 100 μm, from the viewpoints of moldability and transparency. The base material is preferably subjected to a treatment for improving wettability, such as corona, ozone, or flame treatment, on the adhesive layer side.

(3) Adhesive layer The adhesive layer between the base material layer and the barrier layer differs depending on the method of adhering the base material layer and the barrier layer, and adhering both by the dry lamination method can increase the adhesive strength, Although it is preferable at the point which can also improve tearability, in that case, as a contact bonding layer, the two-pack hardening type polyurethane adhesive for dry lamination etc. can be used, for example.
It is also possible to bond the base material layer and the barrier layer together by extrusion lamination. In that case, as the adhesive layer, a polyolefin-based heat-adhesive resin, for example, low-density polyethylene, ethylene-methacrylic acid copolymer, and the like. A simple substance such as a polymer, an ethylene-acrylic acid copolymer, or an ionomer, or a resin blended with an adhesion improver such as a hard resin can be used.

(4) Barrier layer As a barrier layer, the vapor deposition film which vapor-deposited aluminum foil or aluminum oxide or silicon oxide on vapor deposition base films, such as a biaxially-stretched polyethylene terephthalate film, is used. When using the said vapor deposition film, the range of 150-2000 mm is suitable for the thickness of a vapor deposition layer.
Examples of the vapor deposition base film include, but are not limited to, a polyester resin film, a polypropylene film, a polyamide resin film, and the like.
These barrier films not only exhibit high gas barrier properties against oxygen and water vapor, but also exhibit high impermeability to the high-concentration alcohol that is the content in combination with the adjacent anchor coat layer. .

Conventionally, these barrier films do not provide sufficient interlayer adhesion strength in the laminate with the sealant layer, and the alcohol exuded from the contents penetrates the sealant layer and invades the interface between the barrier film and the sealant layer. As a result, it was known that delamination occurred. In addition, there has been a problem in that sufficient initial adhesive strength cannot be obtained at the time of lamination with the sealant layer, and unintended peeling or deviation occurs during the production.
On the other hand, by combining the anchor coat layer made of the specific aqueous dispersion of the present invention, the above problems are solved, and high interlayer adhesive strength and initial adhesive strength are achieved.
Usually, the thickness of a barrier layer becomes like this. Preferably it is 0.01-500 micrometers, More preferably, it is the range of 1-300 micrometers.

(5) Anchor coat layer In this invention, an anchor coat layer is for adhere | attaching firmly the barrier layer which consists of aluminum foil etc., and the sealant layer which consists of polyolefin resin layers.
The anchor coat layer of the present invention contains a specific polyolefin copolymer resin, but is an aqueous dispersion that does not contain a non-volatile aqueous additive, and the polyolefin copolymer resin has a number average particle size of 1 μm or less. For example, it is a layer formed by applying 0.1 to 2 μm of an aqueous dispersion liquid dispersed in an aqueous solvent so as to have a thickness of 50 to 200 nm on the barrier layer and drying by heating.
Here, the polyolefin copolymer resin is a copolymer of a polyolefin-based resin, an unsaturated carboxylic acid or an anhydride thereof, and a (meth) acrylic acid ester, and an unsaturated carboxylic acid in the copolymer resin or The ratio of the anhydride is 0.01-5 mass%, and the ratio of the (meth) acrylic acid ester is 1-20 mass%. Examples of such copolymerization include random copolymerization, block copolymerization, graft copolymerization (graft modification), and the like, and preferably graft copolymerization.

The melting point of the polyolefin copolymer resin is 90 to 110 ° C., and the MFR is 1 to 10 g / 10 minutes.
And since the anchor coat layer acts to strongly react and bond with both layers between the barrier layer made of aluminum foil or the like and the sealant layer made of polyolefin resin layer or the like, the three layers are It can be firmly bonded.
In the present invention, the polyolefin copolymer resin is dispersed in an aqueous solvent so that the number average particle diameter thereof is 1 μm or less, so that the alcohol resistance is improved and a barrier such as an aluminum foil or a vapor deposition film is provided. Adhesive strength between the film and the sealant layer made of a polyolefin resin is increased, and thus stable laminate strength and seal strength can be maintained even when the contents are stored for a long period of time.

On the other hand, when particles having a number average particle diameter larger than 1 μm are used, the alcohol resistance is not improved because the adhesive strength is not sufficient.
Further, the reason why the polyolefin copolymer resin containing 0.01 to 5% by mass of unsaturated carboxylic acid or anhydride and 1 to 20% by mass of (meth) acrylic acid is that the amount of unsaturated carboxylic acid is When the content is lower than 0.01% by mass, sufficient adhesive strength with the substrate is not exhibited, and the adhesive strength is low, so that sufficient alcohol resistance cannot be ensured. On the other hand, when the amount of unsaturated carboxylic acid is higher than 5% by mass, the adhesive strength is sufficiently exhibited, but the compatibility with alcohol increases, and sufficient alcohol resistance cannot be ensured.

Moreover, when the amount of (meth) acrylic acid is lower than 1% by mass, sufficient initial adhesion with an aluminum foil or the like cannot be obtained at the time of lamination, and unintended peeling or deviation may occur during production. On the contrary, when the amount of (meth) acrylic acid is higher than 20% by mass, the alcohol resistance is lowered.
Furthermore, when the melting point of the polyolefin copolymer resin is 90 to 110 ° C., the defense rate against the alcohol of the anchor coat layer is further increased. When the melting point is lower than 90 ° C., since the density of the resin is small, the shielding effect is low and the alcohol resistance is lowered. On the other hand, if the melting point is higher than 110 ° C., sufficient adhesion cannot be obtained when the polyolefin resin layer is laminated by extrusion coating, so that the penetration of alcohol cannot be sufficiently prevented.
In the present specification, the melting point of the polyolefin copolymer resin is a melting temperature measured using a differential scanning calorimeter (DSC) in accordance with the provisions of JIS K7121.

Moreover, when MFR of polyolefin copolymer resin is 1-10 g / 10min, favorable processability is obtained at the time of manufacture of a laminated body, and high adhesiveness with a barrier layer and a polyolefin-type resin layer is obtained. If the MFR is less than 1 g / 10 minutes, sufficient adhesion cannot be obtained when the polyolefin resin layer is laminated by extrusion coating. On the other hand, if it is larger than 10 g / 10 min, film thickness unevenness occurs during coating, a homogeneous surface cannot be formed, and sufficient adhesion cannot be obtained.
In the present specification, MFR is a value measured by the method A under the conditions of a temperature of 190 ° C. and a load of 21.18 N in the method defined in JIS K7210.

The polyolefin copolymer resin used for the anchor coat layer of the present invention is an acid-modified polyolefin resin.
Examples of the polyolefin resin include polyethylene such as low density polyethylene, medium density polyethylene, high density polyethylene, and linear (linear) low density polyethylene, and polypropylene and polybutene. Since adhesiveness is obtained, polyethylene can be particularly preferably used.

  Examples of the unsaturated carboxylic acid component include unsaturated carboxylic acids and anhydrides thereof. Specifically, acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, fumaric acid, croton In addition to acids and the like, unsaturated dicarboxylic acid half esters, half amides and the like can be mentioned. Of these, acrylic acid, methacrylic acid, maleic acid, and maleic anhydride are preferable, and acrylic acid and maleic anhydride are particularly preferable.

Examples of the (meth) acrylic acid ester used for the anchor coat layer of the present invention include an esterified product of (meth) acrylic acid and an alcohol having 1 to 30 carbon atoms. Specific examples of (meth) acrylic acid esters include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, (meth) Examples include octyl acrylate, decyl (meth) acrylate, lauryl (meth) acrylate, octyl (meth) acrylate, dodecyl (meth) acrylate, stearyl (meth) acrylate, and the like. In modification | denaturation of polyolefin resin, only 1 type may be used for (meth) acrylic acid ester and it may use 2 or more types.
In the present invention, “(meth) acrylic acid ester” means “acrylic acid ester” or “methacrylic acid ester”.

The anchor coat layer of the present invention is excellent in adhesiveness to the barrier layer and the polyolefin resin layer by being thinly applied so that the thickness when dried is 0.1 to 2 μm.
The reason why the thickness of the anchor coat layer when dried is 0.1 to 2 μm is that when the thickness is less than 0.1 μm, sufficient adhesion strength with the melt-extruded polyolefin resin cannot be obtained. On the other hand, when the thickness is greater than 2 μm, the coating amount is the same as that of the dry laminate adhesive, which increases the cost and cannot be used for actual production.

In addition, non-volatile aqueous additives such as emulsifiers remain in the coating film even after drying, and even if a small amount, it has a great effect on the adhesive interface and reduces adhesion and water resistance. In the coating layer, a nonvolatile aqueous auxiliary agent such as an emulsifier is not added for the purpose of promoting aqueous formation or stabilizing the aqueous dispersion in the production process of the aqueous dispersion. Therefore, delamination does not occur, and the adhesiveness with the barrier layer is excellent and the adhesiveness with the polyolefin resin layer is also excellent.

The coating amount of the aqueous dispersion used to form the anchor coat layer, 0.1 g / m ² or less, more preferably 0.05 to 0.1 / m ^2. This is 1/10 or less compared with the amount of normal adhesive used, and the low molecular weight trace component contained in the aqueous dispersion hardly passes through the polyolefin resin layer. Trace components contained in the body do not leak into the contents and can prevent deterioration of the contents.

(6) Polyolefin-based resin layer The polyolefin-based resin layer that functions as a sealant layer can use polyolefin-based resins having various sealant properties that can be melted by heat and fused to each other.
Examples of the polyolefin resin suitably used in the present invention include one kind of low density polyethylene, medium density polyethylene, high density polyethylene, linear (linear) low density polyethylene, polypropylene, ethylene-propylene copolymer, and the like. Examples thereof include resins composed of more than that, and low density polyethylene and linear low density polyethylene are particularly preferably used for reasons such as sealing properties, alcohol resistance and adhesion to the anchor coat layer.

  The thickness of the polyolefin resin layer is not particularly limited, but is preferably 5 to 500 μm, more preferably 10 to 250 μm. If the thickness is less than 5 μm, sufficient laminate strength cannot be obtained even if heat-sealing, and the product does not function as a packaging bag. When it is thicker than 500 μm, the cost increases and the film becomes hard and workability deteriorates.

In the present invention, it is particularly desirable to melt-extrude a polyolefin-based resin and provide the resin layer on the anchor coat layer, thereby achieving high interlayer adhesion strength.
In addition, the polyolefin resin layer of the present invention is appropriately added with one of additives such as an antioxidant, an ultraviolet absorber, a light stabilizer, an antistatic agent, an antiblocking agent, a flame retardant, a crosslinking agent, and a colorant. You may add seed | species thru | or 2 or more types.

The polyolefin-based resin layer may be formed by a method in which the same polyolefin-based resin, for example, low-density polyethylene, linear low-density polyethylene, or the like is used as an adhesive layer and is extruded and laminated on the anchor coat layer. The thickness of the adhesive layer is preferably 0.1 to 200 μm, more preferably 1 to 100 μm.
When the film thickness is not more than the above range, it is difficult to extrude easily and the adhesive strength is not exhibited. When the film thickness is in the above range or more, problems such as adhesive strength are solved, but the cost increases due to excessive use of the resin.

The adhesive layer of the present invention is preferably low-density polyethylene or linear low-density polyethylene from the viewpoint of extrusion suitability and adhesiveness.
Moreover, the unevenness | corrugation whose height is several micrometers-20 micrometers can also be provided in the whole surface of a polyolefin-type resin layer like the laminated body 20 shown in FIG. With this configuration, the hand cutting property can be further enhanced.
In order to provide such irregularities, lamination of polyolefin resin layers was performed by an extrusion coating method, and irregularities capable of forming irregularities with a height of several μm to 20 μm were provided on the cooling roll used at that time. By using a cooling roll, it is possible to laminate a polyolefin-based resin layer having unevenness with a height of several μm to 20 μm on the surface with good productivity.

只 Even with the extrusion laminating method, it is possible to provide unevenness with a height of several μm to 20 μm on the entire surface of the polyolefin resin layer. It is necessary to form the unevenness on the surface of the polyolefin resin film by a method such as hot embossing after the polyolefin resin film is pasted together by an extrusion laminating method using the same polyolefin resin. Since the manufacturing process of a laminated body increases correspondingly, productivity falls and it is disadvantageous in terms of economical efficiency.

  The unevenness with a height of several μm to 20 μm provided on the entire surface of the polyolefin resin layer is opened by tearing the bag by hand when taking out the sealed contents filled in a packaging bag made of a laminate. In order to improve the hand-cutness at the time, for the purpose, the concave and convex portions, for example, small convex portions such as a truncated pyramid shape and a pyramid shape are densely arranged in a grid shape, and the concave portions It is more preferable that the shape is a shape that is linearly connected to the tearing direction of the bag, or an uneven shape that is formed so that the elongated hook-shaped convex portions are closely arranged and the concave portions coincide with the tearing direction.

Moreover, although the unevenness | corrugation height changes also with the thickness of a polyolefin-type resin layer, the height of several micrometers-20 micrometers is preferable, and the height of 10 micrometers-20 micrometers is still more preferable.
When the height of the unevenness is several μm, for example, smaller than 7 to 8 μm, it becomes difficult to obtain the effect of improving hand cutting properties, and when the height of the unevenness exceeds 20 μm, the uniformity of the heat seal part is easily impaired. Therefore, it is not preferable.

(7) Print layer In the present invention, a desired print pattern layer can be formed between any of the layers constituting the packaging material. As the printed pattern layer, for example, an ink composition such as a normal gravure ink composition, an offset ink composition, a relief printing ink composition, a screen ink composition is used on the base material layer. A printing method such as a printing method, an offset printing method, a letterpress printing method, a silk screen printing method, or the like is used, and for example, a desired printing pattern made up of characters, figures, patterns, symbols, and the like can be formed.

The printed layer can be printed on a plastic substrate when a desired printed pattern such as characters, figures, symbols, patterns, patterns, etc. is printed on the surface or when a transparent plastic substrate is used as the substrate layer. You may perform reverse printing.
Next, the present invention will be described with reference to examples.

Example 1
An aluminum foil having a thickness of 7 μm was laminated on a biaxially stretched polyethylene terephthalate film having a thickness of 12 μm through low-density polyethylene coated with a two-component curable urethane anchor coating agent and melt-extruded at 330 ° C.
Next, a polyethylene copolymer resin (melting point: 105 ° C., MFR: 1-7 g / 10 min) containing 2% by mass of maleic anhydride and 18% by mass of ethyl acrylate as an anchor coat layer on the non-laminated surface of the aluminum foil in water. Using a dispersed aqueous dispersion (dispersed resin number average particle size 0.6 μm, no emulsifier), this was applied so that the thickness when dried was 0.5 μm, dried by heating and anchor coat layer Formed.
Next, on this anchor coat layer, low density polyethylene is extruded at an extrusion temperature of 330 ° C. to a thickness of 25 μm, and a polyolefin resin layer (sealant layer) is laminated by an extrusion laminating method to form the packaging bag of the present invention. A laminate for inclusions was produced.
Next, the two laminates were overlapped so that the sealant layers were opposed to each other, and heat-sealed in a four-side seal form so as to be a rectangle having a length of 170 mm and a width of 130 mm, thereby producing an alcohol-containing packaging bag of the present invention. .

(Example 2)
An aqueous dispersion in which a polyethylene copolymer resin (melting point 95 ° C., MFR 2-9 g / 10 min) containing 3% by mass of maleic anhydride and 12% by mass of ethylene acrylate is dispersed in water as an aqueous dispersion for forming the anchor coat layer. Use dispersion (number average particle diameter of dispersed resin 0.6 μm, no emulsifier), and use linear low density polyethylene as resin to form polyolefin resin layer (sealant layer), thickness 25 μm A packaging bag for alcohol-containing material of the present invention was produced in the same manner as in Example 1 except that the bag was extruded.

(Comparative Example 1)
Instead of extruding and laminating a polyolefin resin layer via an anchor coat layer, the two-part curable polyurethane adhesive for dry lamination is applied to the non-laminated surface of the aluminum foil at a coating amount of 3.0 g / the coating is m ^2, then, except that the linear low density polyethylene film having a thickness of 70μm was laminated by dry lamination method, in the same manner as in example 1 to prepare a laminate and the packaging bag.

(Comparative Example 2)
A laminate and a packaging bag were prepared in the same manner as in Example 1 except that a urethane-based anchor coating agent (A3210 / A3075, manufactured by Mitsui Chemicals, Inc.) was used as the anchor coat layer.

(Comparative Example 3)
Instead of laminating a polyolefin resin layer via an anchor coat layer, a laminate was obtained in the same manner as in Example 1 except that EMAA was extruded to a thickness of 25 μm at an extrusion temperature of 295 ° C. on the non-laminated surface of the aluminum foil. And the packaging bag was produced.

(Comparative Example 4)
A laminate and a packaging bag were produced in the same manner as in Example 1 except that an aqueous dispersion in which a polyethylene copolymer resin having a melting point of 80 ° C. was dispersed was used as the aqueous dispersion for forming the anchor coat layer.

(Comparative Example 5)
A laminate and a packaging bag were produced in the same manner as in Example 1 except that an aqueous dispersion in which a polyethylene copolymer resin having a melting point of 120 ° C. was dispersed was used as the aqueous dispersion forming the anchor coat layer.

(Comparative Example 6)
A laminate and a packaging bag are produced in the same manner as in Example 1 except that an aqueous dispersion in which a polyethylene copolymer resin having an MFR of 0.8 g / 10 min is used is used as the aqueous dispersion for forming the anchor coat layer. did.

(Comparative Example 7)
A laminate and a packaging bag were produced in the same manner as in Example 1 except that an aqueous dispersion in which a polyethylene copolymer resin having an MFR of 15 g / 10 min was dispersed was used as the aqueous dispersion for forming the anchor coat layer.

(Comparative Example 8)
The laminate is the same as in Example 1 except that an aqueous dispersion in which a polyethylene copolymer resin having an acrylic ester content of 0.5% by mass is used as the aqueous dispersion for forming the anchor coat layer. And the packaging bag was produced.

(Comparative Example 9)
A laminate and a package in the same manner as in Example 1 except that an aqueous dispersion in which a polyethylene copolymer resin having an acrylate amount of 25% by mass was used as the aqueous dispersion forming the anchor coat layer. A bag was made.

(Comparative Example 10)
A laminate and a package in the same manner as in Example 1 except that an aqueous dispersion in which a polyethylene copolymer resin having a maleic anhydride amount of 0% by mass was used as the aqueous dispersion forming the anchor coat layer. A bag was made.

(Comparative Example 11)
A laminate and a package in the same manner as in Example 1 except that an aqueous dispersion in which a polyethylene copolymer resin having a maleic anhydride amount of 10% by mass was used as the aqueous dispersion forming the anchor coat layer. A bag was made.

(Evaluation test)
(1) Alcohol resistance and initial adhesion test method The initial adhesion (laminate strength of the aluminum foil and the sealant layer) was measured for each of the packaging bags of Examples 1-2 and Comparative Examples 1-11. Next, a storage test of the contents was performed under the following test conditions, and the presence or absence of delamination of the packaging bag after the test, in particular, the sealant layer was examined. Further, when the sealant layer was not peeled off, the laminate strength between the aluminum foil and the sealant layer was examined.
Test conditions 1: Each packaging bag was filled with 200 ml of an 80% by weight aqueous solution of ethyl alcohol as a content, sealed with a degassing seal, and then subjected to a storage test at 60 ° C. for one month.
Test condition 2: Absorbent cotton impregnated with 80% by weight of ethyl alcohol as a content in each packaging bag was filled in a sufficient amount, sealed with a degassing seal, and then subjected to a storage test at 60 ° C. for one month. .

The laminate strength of the sealant layer was measured according to JIS K 6854 using a tensile test apparatus (Tensilon) at a tensile speed of 50 mm / min, 90 degrees direction, and a sample width of 15 mm.
The results are shown in Table 1.

(2) Test method of hand tearability at the time of opening About each packaging bag of Examples 1-2 and Comparative Example 3 after performing a storage test in the above-mentioned alcohol resistance test, one side of the upper part of the packaging bag A notch is made in the heat seal part of the bag, and the top of the bag is torn by hand in the lateral direction starting from the notch, the magnitude of tear resistance at the time of tearing, the linearity in the tear direction, and the sealant layer at the torn tear edge Whether or not peeling occurred was examined in an integrated manner, and hand cutting properties were evaluated according to the following criteria.

<Evaluation criteria for hand cutting ability>
Excellent: Tear resistance is small, tear direction is almost linear, and sealant layer is hardly peeled off at the tear edge Good: Tear resistance is moderate, there is no large bending in the tear direction, and sealant at the tear edge Slight peeling of the layer.
Inferior: Tear resistance is slightly large, the tear direction is bent, and the sealant layer at the tear end is slightly peeled. The results are shown in Table 2.

(Evaluation results)
As shown in Table 1, the packaging bags of Examples 1 and 2 maintain excellent laminate strength even after being stored at 60 ° C. for 1 month under various conditions, and against high-concentration alcohol. And showed excellent resistance. Further, as shown in Table 2, it had a sufficiently good hand cutting property for use as a packaging bag.
On the other hand, although the packaging bags of Comparative Examples 1-2, 9, and 11 showed sufficiently high laminate strength before the alcohol storage test, they significantly decreased after the storage test, and the sealant layer was peeled off.
Although the packaging bags of Comparative Examples 3 to 5 were not peeled off, the laminate strength was small or decreased significantly after the storage test. Furthermore, the packaging bag of the comparative example 3 was inferior to hand cutting property.
The packaging bag of Comparative Example 6 was inferior in alcohol resistance because sufficient adhesion was not obtained when the sealant layer was laminated. In the packaging bag of Comparative Example 7, the anchor coating agent flowed during lamination, and sufficient adhesion was not obtained.
The packaging bags of Comparative Examples 8 and 10 were inferior in initial adhesion, and sufficient laminate strength could not be obtained.

DESCRIPTION OF SYMBOLS 1 ... Base material layer 2 ... Adhesive layer 3 ... Barrier layer 4 ... Anchor coat layer 5 ... Polyolefin resin layer 6 ... Concavities and convexities 10 and 20 having a height of several μm to 20 μm ... Laminate

Claims (2)

A packaging bag for packaging a liquid having an alcohol concentration of 50% by mass or more, or an impregnated product of the liquid, the packaging bag comprising at least a base material layer, an adhesive layer, a barrier layer, an anchor coat layer, and a polyolefin resin layer. It is formed of a laminate that is laminated in this order,
The barrier layer is an aluminum foil, or a deposited film formed by depositing aluminum oxide or silicon oxide on a base film,
The anchor coat layer is an aqueous dispersion in which a polyolefin copolymer resin is dispersed so that the number average particle diameter thereof is 1 μm or less, and the aqueous dispersion does not contain a non-volatile aqueous agent. The aqueous dispersion formed is applied to the surface of the barrier layer so that the thickness upon drying is 0.1 to 2 μm, and is formed by heating and drying to improve the barrier property against alcohol,
The polyolefin copolymer resin contains 0.01 to 5% by mass of an unsaturated carboxylic acid or an anhydride thereof, 1 to 20% by mass of a (meth) acrylic acid ester, and a melting point of 90 to 110 ° C. The melt flow rate is 1-10 g / 10 min,
The polyolefin-based resin layer is formed by a method of extruding and coating a polyolefin-based resin on the surface of the anchor coat layer, or a method of extruding and laminating a polyolefin-based resin film using a similar polyolefin-based resin. A packaging bag for alcohol-containing materials.   The base material layer is a biaxially stretched polyethylene terephthalate film, the barrier layer is an aluminum foil, and the polyolefin resin layer is a layer made of low-density polyethylene or linear low-density polyethylene. The packaging bag for alcohol-containing materials according to 1.

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